Habitat use and population dynamics of the Azure-Winged Magpie ...

during the breeding season. After breeding, the adult birds switch to fruit and adult moths. The
magpies have also been seen to take food scraps from the field station kitchen (Gantulga B, pers.
comm.).
2.1.5 Social behaviour
C. cyanus is a sociable and gregarious bird. The flocks vary in size; they are generally in family
groups during breeding season, but will form winter flocks, sometimes exceeding well over 100
birds in China and Japan. The flocks also congregate to form large communal roosts in winter
(Hosono, 1968; Madge & Burn, 1994). Territoriality is reported in the European (Snow et al.,
1998) and Japanese populations (Komeda et al., 1987), where flocks defend extensive territories
against other flocks throughout the year; however, the Spanish colony studied by Valencia et al.
(2003) was not territorial. Birds are non-migratory but can flock and disperse up to 15kms in
winter (Hosono, 1968; Gantulga, 2010).
2.1.6 Breeding biology
Eggs are laid between early April and late July, depending on the altitude (Snow et al., 1998;
Valencia et al., 2002). In central Spain, eggs are laid from early April to late May at lower
altitudes (300 m) while at higher altitudes (1250 m), eggs are laid early June to late July. In
southern Spain and east Portugal, eggs are laid end of April to early or mid-May. In the Far East,
egg-laying is usually around late May and June (Madge & Burn, 1994). Pairs typically produce
one brood per season, although second broods have been reported occasionally in Spain
(Valencia et al., 2000) and Asia (Madge & Burn, 1994). Replacement clutches are laid as a result
of earlier brood loss if conditions allow (Valencia et al., 2000; Gantulga et al., in review).
The birds nest socially, with nests in loose colonies, normally not more than one nest per tree
(Madge & Burn, 1994; Snow et al., 1998); however, colonies can be quite large, with as many as
70 nests. Nests are usually located at the fork of a branch towards the edge of tree crown, up to
12m above ground (Snow et al., 1998). In Khonin Nuga, Northern Mongolia, nests were always
close to tree trunks or at the fork of several criss-crossing branches, and never exceeded 2m in
height (pers. obs.). Nests are usually built from a rough, loose foundation of twigs, layered inside
with earth, mud or dung, shaped to form a bowl about 2-5cm thick. The nest is then lined with
soft material such as moss, lichen, animal hair, feathers etc (Snow et al., 1998).
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